Controller



Feb. 28, 1933. c, E, MASON ET Al.

CONTROLLER Filed Sept. 15, 1930 Ina/e n30 WSJ" Maso Tv, ff. .mt-vow'1.11, 6M, Murr Mm. ty@

Patented Feb.y 28, `1193.3

l 'v A1,899,705

f UNrrED-.sTATEs PATENrLoFl-*lcn E. IASON'IAND ARNOLD DIXON, O FFOXBOBO,

T THE FOXBORO COMPANY, 0F FOXBORO, MASSACHUSETTS, A .GQfPORATIOl-T 0FIASSACHUSETTS y I This invention relates to controlling the flow ofiiuid to a locus to establish and malntain at a. predetermined value avariable condition at 'the lpcus.` The particular object is' to providecooperating means for effecting a major flow of Huid by means of whichthe variable condition may be brought approximately to the desiredvalue, either initially or in the event of a major fluctuation, and

. a minor flow closely to4 control conditions.

An application of our invention is the con-- means of suitablethermostatic ccnsteam to a chamber to be l an installation with parts insection; and

' Fig. 2 is an enlarged section through the valve which controls theflow of iiuid.

In the exemplary embodiment of our in- .vention shown in the drawing theflow of steam to chamber' is controlled by a single valve 5 in the steampipe 7. The valve', however, is provided with ports such that it mayfunction as a valve of large opening to provide a maj or low of steamanda valve of relatively small opening to provide a minor iiow.

Herein the valve proper (seeFig. 2) has a body in the form of avertically reciprocating hollow piston 9 which is pro'vided withgraduated ports having a minor'port portion 11, herein shown astriangular in form, with'a major port portion 13, herein rectangularferm 'and of markedly increased ybase lso that at least Vone Side of thecombinedopening exhibits a marked step or 'break as shown in theligure.` Supposing the valve tb lift from the positionshown in Fig. 2, agradually increasing How initially takes' place as the triangle 11passes the wall 15. Then as the upper boundary of the port portionsv 13passes thispointa suddenly increased iow is initia The valve may beoperated bymeans of CONTROLLER l applicati@ md september 15, 1930.serial no.' 482,126.

ing the'valve high pressure iiuid may be supplied tothe -motor' fromsupplypipe 19 through a control head H. P. `The control head embodies asuitable valve 21 for alternatively opening and closing thecommunication between the source of pressure Huid at 19 and theAmotor'17, the valve being suported on a hollow stem 23 which is carriedvthe expansible diaphragms 25 havin a MASSACHUSETTS, assIeNons I 1.asuitable motor 17, herein shown as a'well `known type' of diaphragmmotor. For openb eeding or exhaust port inthe adjusta le"A nozzle 27controlled by a valve 29 operated by a suitable thermometricallyresponsive device 31 connected with thethermometerbulb 33 in'chamber 3.TheA construction f the control couple27-29 maybe substantially' -asshown in the patent to Dixon 1,582 868,-

April 27, 1926, and need 'not be more fully described herein.

With the parts in the position shown, pressure fluid iows freely throughthe head H. P.

.to motor 17 and the valve is opened wide.

lFluidis also escaping through the hollow valve stem 21 and throughbleeding port 27 and the. diaphragms 25 are collapsed as they are ventedto the atmosphere. The chamber rapidly heats up due to the great ow offluid through the'port portions 13\of valve 5. As the temperatureapproaches the desired control point and at a predetermined intervaltherefrom, valve 29 closes, pressure builds up in diaphragms25 andvvalve 23 `moves to the right, shuttingI oif further supply of Huid frompipe 19. The construction of the valve, however, as seen from thefigure, is such that. no exhaust passage is open to the atmosphere as iscustomary in devices of this kind. The valve 21, in other words, is asimplevalve,

merely opening or interrupting communication between two points.

Control of the valve 5 is then taken over i I by cooperating mechanismwhich controls the iiow of' fluid at a relatively low pressure,

for instance, from ipe. 19 through .a reduc- `ing valve 35 or similarmeans. for restricting the free iow of fluid, Athrough vipe 37 controlh'ead L. P. to the motor "l The control head L. P. embodies a supply andwaste valve 39 carried by a hollow stem 41 mounted ytion with a bleedingon diaphragms 43 which are in communicaort in nozzle 45 With whichcooperates the valve 47. In the. example of the invention shown thevalve 47 serves `to throttlemore or less the exhaust ized by'exhaustthrough hollow stem 41 ofthe valve 39 `and exhaust port in nozzle 45,the reduced pressure inJmotor 17 permits valve 5 partially to close andthe triangular portion 2b 11 of the port functions. With the valve 47the motor 17 and in part bleeds through the open uid at relatively lowpressure flows to control couple 45-47. As, however, the temperatureapproaches the desired point, valve 47 lthrottles more or less thecontrol point permitting pressure to build up in the diaphragms 43.Valve 39 is shifted more or less to the left, throttling the -flow offluidy to themotor 17 and permitting partial eX- haust of the motorthrough the partly opened Waste port 51 at the left of the valve 39 andpermittingtthe main valve 9 to move toward the closed position. Finally,if the valve 47 is completely closed, the iiow of fluid to the motorl iscompletely stopped, the motor is4 exhausted to. atmosphere and the valvecompletely closed.

We are aware that the invention may be embodied in other specific formswithout departing from the spirit or essential attributes thereof, andWe therefore desire the present embodiment tobe considered in allrespects as illustrative and not restrictive; reference being had totheappended claims rather than l to the foregoing description to indicatethe scope of the invention.

We claim: 1. Means for controlling the flow of uid toa locus thereby toaffect the value of a variable condition at the locus comprising, in

. combination with means responsive to the variable condition at thelocus', a valve having ports of marked different area, amotor for movingthe valve-successively to bring into action said ports and controlcouples governed by said responsive means to supply pressure Huid atrespectively different pres-4 sures to. said motor.

2. Means for controlling the flow of fluid to a `locus thereby to affectthe value of a variable condition at the locus comprising,

in combination with means responsive to the variable condition at thelocus, a valve having a port at least one side of'which defines a markedstep, a motor for moving the valve successively to render leffective theportions to a locus thereby to affect thev value of a vay riablecondition at the locus comprising a valve having a graduated p-ort,a-motor for operating the valve, control mechanism for supplyingrespectively operating fluid at.;

relatively high and lovs7 pressures to the motor and control couplesgoverning the same and means responsive to the iiuctuations of thevariable at the locus for operating the Couples.

4. Means for controlling the flow of Huid to a locus thereby to affectthe value of a @variable condition at the locus comprising valve meanshaving relatively large and small ports, motor means for actuating thevalve means', a control mechanism for supplying pressure fluid to themotor means to bring into action the large port, a control mecha- -nismfor supplying pressure fluid to the motor means to bring into actionvthe small port, and control couples governing said mechanisms operatingrespectively at different values of the variable condition at the locus.

5. lMeans for controlling a flow of fluid .to al locus whereby tomaintain at a predetermined value a variable condition at the locus,

asl

comprising valve means having large and small ports, means effectivewhen the variable has a value determinately different from saidpredetermined value for operating said valve means to work the largeport, and cooperating means effective when the variable is substantiallyof such predetermined Ivalue for operating said valve means to work thesmall port.

6. Means for controlling a 4flow of fluid to alocuswhereby to maintainat a predetermined value a variable conditon at the locus, comprisingvalve means having large and small ports, means effective when thevariable has a value determinately different from said predeterminedvalue for operating said valve means to open or shut the ,large port,land cooperating means effective when the variable more closelyapproaches such predetermined value to operate said valve means to worksaid small port with a throttling action. v

7. In combinationl with a pressure operated motor, means for supplyinfluid thereto comprising a simple valve or opening or` closingcommunication of said motor with a source of fluid at relatively hi hpressure, a supply and Waste valve for a mitting to -or exhausting fromsaid motoxfuid at relatively low pressure, means for moving said valvessubject to4 the several pressures, bleeding ports for said means, valvesfor said ports and means responsive tothe fluctuations of' a variablewhich is affected by the operation of said motor, said means eiective'toclose the last mentioned valves at diferent values thereof.

8. In combination with a pressure operated motor, means for supplyingiluid thereto comprising a simple valve for opening or closingcommunication of said motor witha source/of fluid at relatively hi hpressure, a supply and waste valve for' amitting to or exhausting fromsaid motor fluid at relatively low pressure, means for moving saidvalves subject to the several pressures, bleeding ports for said means,a valve responsive to the fluctuations of a variable which is affectedby the operation of said motor, said valve arranged to close thebleeding port pertaining to the high pressure s stem at a predeterminedvalue of thefvaria le, and a valve responsive to the fluctuations of thevariable arranged to throttle the port pertaining to the low pressuresystem as 'a second determinately different value is approached.

Y 9. Means for controlling the flow of fluid toa locus to'establish andmaintain at a predetermined value a variable condition at thelocuscomprising a valve for the fluid, motor means for moving the valve, andcooperating controllers responsive to the fluctuations of the variablefor governing said motor, vthe one going out of action when saidvariable determinately diiers. from said predetermined value and thendetermining a certain opening of said valve andthe other governing themotor between said position .and closed position of the valve as thevariable approaches said predetermined value.

10. Means for controlling the flow of fluid to a locus thereby to affectthe value of a variable condition 'at the locus comprising a valve, amotor for-moving the same, means to supply pressure fluid to the motorat relatively high and low pressures to open the valve to greater orless vdegree comprising high and low pressurev4 control mechanisms andcontrol couplesgovernin lsaid mechanisms and operating respective y atdifferent values 'of the variable at the locus.

11. Means for controlling the' How of fluid to a locus to establishandfmaintain at a predetermined value a variable condition and the locuscomprising valve means f having ports of large capacity and smallcapacity, 55 motor means for operating the' valve means,

and control mechanisms for energizing the motormea scomprising elementsresponsive tothe iiucxations of the-variablmne eiectivewhen saidvariable reaches a value determinately die'rent from 4said predeterminedvalue torenergize the lmotor means to close the port of large capacityand the other effectiveas said variable approaches the predeterminedvalueJto engize the motor means 65 to close the port of sm capacity.

'- .12. Means as described inclaim 11 wherein the port of smallcapacityis a graduated one.

13. Means as described in claim 11 wherein the ports are organized in asingle valve to provide an abrupt change in flow as the 7 valve travelsto open-successively the small and large ports.

, 14. Means for controlling a flow of fluid."

to a locus whereby to establish and maintain at a predetermined value avariable condition at the locus comprising valve means having large andsmall ports, motor means forl opening the same, a source of pressurefluid for operating the motor means, valve mechanism to control the flowof fluid to the motor means, pressure operated means for shifting thesame, a pair of bleeding. ports for said pressure operated means, meansbetween .the ports restricting free flow of Huid through one as comparedwith the other, a valve for said other port responsive to close thesaine when the variable reaches a value determinately diierent from saidpredetermined value whereby to change pressure conditions in the systemand a valve for said one port responsive to close the same as thevariable approaches said predetermined value.

15. In combination with a pressure operated motor, a source of pressureHuid for ope-rating the same, valve mechanism to control the -ow of Huidto the motor, pressure operated meansfor shifting the same, a pair ofbleeding -ports for said pressure operated means, means between theports for restrict-v ing free flow of fluid through one as.v comparedwith the other, and'valve means adapted successively to close irst said.other port whereby to change pressure conditions in the system andthereafter said one port. In testimony whereof, we have signed our namesto this specification.

CLESSON E. MASON. ARNOLD M.A DIXON.

